Needles in haystacks -

Greetings, I work in the IT dept of a large organization - yesterday I needed help with a Project. 3 people in my group (my group is a subset of the organization, the other subsets are unrelated functions) are familiar with a particular piece of hardware related to the Project, and were all in meetings when I reached out to them. A member of the Team I reached out to responded later with the remark..."Wow! you needed help when we were all in a meeting?...what are the odds of that happening?

My question is : should the answer be the 3/(Total number of employees in org) = (3/@1000) * 100 = 0.3% or 100-(1/(number of employees expected to know about the project)) = 1/3 * 100 = 66.7% or is it a more complex dependency.